Module: Zonal Grid Statistics
Copyrights (c) 2005 by Volker Wichmann
Menu: Geostatistics > Grid
Description
The module can be used to create a contingency table of unique condition units (UCUs). These units are delineated from a zonal grid (e.g. sub catchments) and optional categorial grids (e.g. landcover, soil, ...). It is possible to calculate simple statistics (min, max, mean, standard deviation and sum) for each UCU from optional grids with continious data (e.g. slope). The number of input grids is only limited by available memory. The module has four different modes of application: (1) only a zonal grid is used as input. This results in a simple contingency table with the number of grid cells in each zone. (2) a zonal grid and additional categorial grids are used as input. This results in a contingency table with the number of cells in each UCU. (3) a zonal grid and additional grids with continuous data are used as input. This results in a contingency table with the number of cells in each zone and some simple statistics for each zone. The statistics are calculated for each continuous grid. (4) a zonal grid, additional categorial grids and additional grids with continuous data are used as input. This results in a contingency table with the number of cells in each UCU and the corresponding statistics for each continuous grid.

Depending on the mode of application, the output table contains information about the category combination of each UCU, the number of cells in each UCU and the statistics for each UCU. A typical output table may look like this:
ID ZoneID 1stCatID 2ndCatCount UCUMIN 1stContMAX 1stContMEAN 1stContSTDDEV 1stContSUM 1stCont
0 2 6 6 708.5 862.0 734.5 62.5 4406.8
0 3 4 106 829.1 910.1 848.8 28.5 89969.0

Parameters
NameTypeIdentifierDescriptionConstraints
Input
Zone Grid Grid (input)ZONESGrid defining the zones to analyse. This grid also acts as a mask. Coding: no-data / categorial values.
Categorial Grids (*)Grid list (optional input)CATLISTGrids used to delineate the UCUs. Coding: no-data / categorial values.
Grids to analyse (*)Grid list (optional input)STATLISTGrids with continuous data, statistics are calculated for each grid. Coding: no-data / continuous values.
Output
Result TableTable (output)OUTTABSummary table.
(*) optional